Improvement in rock-drills



D, KENNEDY. Rock-Drills.

N0. 143,355, Patented September30,l87 3.

L. IIII I I El@ S NITED STATES PATENT OFFICE.

. DANIEL KENNEDY, OF BROOKLYN, NEW YORK.

iMPRovEMENTm RocK-DRuLs. i

Specification forming part of Letters Patent N o. 1113.355, dated September 30, 1873 application filed 1 March 24, 1873.

To all whom it may concern Be it known thatI, DANIEL KENNEDY, of Brooklyn, in the county of Kings and State of New York, have invented an Improved Rock- Drill, of which the following is a specification:

Figure l is a` vertical longitudinal section of my improved rock-drill, taken on the plane of the line C C, Fig. 2. Fig. 2 is a vertical transverse section of the same,'talren on the plane of the line K K, Fig. l. Fig. 3 is a top view, partly in section, of the same. Fig. 4 is a face view of the nut which embraces the piston; and Fig. 5, a face view of the xed ratchet with which such nut is in contact.

Similar letters of reference indicate corresponding parts.

The object of this invention is to produce a simple and effective rock-drill, to be operated by steam, compressed air, or otherwise, and which shall be at once convenient for use, light, and effective. The invention consists, princip ally, in a novel construction of the steampiston, which passes, during its reciprocating motion, through an intermittingly rotary nut that engages with spiral grooves or threads on said piston, to gradually turn the same and feed the drill with which the same is connected. There are other spiral grooves cut into the plunger to conduct steam toward its upper end, for the purpose of obtaining full steam-pressure on the downward stroke. My invention also consists in providing the nut aforementioned with ratchet-teeth, which engage with the teeth of a fixed ratchet, or with a spring-pawl, so that thereby the nut is prevented from turning in one direction, but permitted to turn in the other. My invention furthermore consists in arranging a piston within the main piston aforementioned, the latter being made hollow to receive the former. This internal piston serves to regulate the motion of the steamvalve, and also the feed mechanism, by simple means.

In the accompanying drawing, the letter A represents the steam-cylinder of my improved ro cli-drill, andB is the plunger working therein. This cylinder A is, by a projecting arm, a, connected with a feed-screw, D, which feed-screw is secured into the stationary frame C. A nut, b, fitted around the feed-screw into the connecting-arm a, serves to feed the cylinder down when the nut b is turned. The cylinder therefore'is, with its plunger, entirely suspended lB', and the cylinder A is smaller in diameter at its upper than at its lower part, to properly receive and fit the two parts of the plunger or piston. By an outwardly-projecting rod, F, the piston connects with the drill. G is a steam-chest, secured to the side of the cylinder A, and provided with a slide or other steam valve, H, by which the admission of lsteam-to the cylinder is regulated. At the junction of the wider and narrower parts of the cylinder A there is fitted into the same a nut, I, which, on its upper face, has ratchet-teeth cut into it, as indicated in Fig. 4, and is with these' ratchetteeth in contact with similar ratchet-teeth, d, that are stationarily formed in the cylinder, or with a spring-pawl therein provided. The nutbody embraces the smaller part lB of the piston, and enters with its thread e one or more spiral grooves or threads, f, which are cut into said smaller part B' of the piston. When Vsteam is admitted against the lower end of the piston through the part g, the piston is forced upward, and by its spiral grooves turns the nut I in the direction of the arrow shown in Figs. l and 2, the friction of the nut being less than that acting on the piston-rod in its stuffing-boxes, &c., so that the piston will readily cause the nut to turn in the manner described, the ratchet-teeth on the nut being permitted to turn in such direction, but not in the other. When the piston has reached its uppermost position, as shown in Fig. l, and steam is admitted to its top through the port h, it is forced down, and will' then have the tendency to turn the nut inthe opposite direction. The nut, being by the ratchet-teeth prevented from so turning, will then cause the pisv ton to be turned in the direction of the arrows, andin accordance with the degree of Obliquity of the groove j'. By this means the requisite turning of the drill, which connects with the piston, is obtained. The small part B' of the piston has, further, grooves 'i out into it from end to end, for conducting the steam to its uppermost end during the downward stroke of the piston, so that the full face of the entire piston will, during such downward stroke,- receive the steam-pressure, the entire amount of power being thus applied. Within the small part B' of the piston, which is tubular, as shown in Figs. l and 2, is fitted a small piston, J, whose rod L extends upward through a packing in the uppermost end of the main piston B', and through a gland, j, in the upper part of the cylinder, and which, above said gland, carries a ring or disk, Z. By means of this ring or disk Z the inner piston J causes the vibration of a forked lever, M, which is pivoted at m to the cylinder, and which, by a rod, n, connects with the slidevalve H. When the plunger J moves downward the ring or disk Zstrikes the lower arm of the forked lever M and trips it, so as to move the slidevalve upward, while, diuing the upward stroke of the piston J, the upper arm of the forked lever is struck to cause the slide-valve to move downward. By this means the requisite change in the admission of steam is produced. The hollow part B' of the piston B is perforated to admit steam into its interior, so that by such steam-admission the plunger J may, to a certain degree, be aiected. When the piston B is in its lowermost position the piston J reaches nearly to the upper end of the hollow part B', as shown in Fig. 2. When thereupon steam is admitted against the under side or" the piston B the piston J remains stationary, until the lower part of the tubular piston B' strikes it and carries it up with it to trip, at the end 'of its stroke, the lever M. When thereupon thc piston B is moved down the piston J will again be held stationary, until it is carried down by the upper end of the hollow piston B', the steam-admission to the hollow piston serving to keep the same stationary in the positions indicated. By thus regulating the motion of the piston J and lever M, I obtain a steam-cushion at the end of each stroke of the pistons B and J, and prevent abrupt terminations of such strokes. The disk or ring l serves, during its downward motion, also to force outward a spring-pawl, N, which catches into a ratchet-wheel, a, that is mounted upon the feed-screw D, thus imparting intermittent rotary motion to said feed-screw, and causing the cylinder A, with its appendages, to be gradually fed downward.

What is here claimed, and desired to be se cured by Letters Patent, is-

1. The piston of a rock-drill made of a large part, B, and a smaller part, B', the part B' being grooved, as at fi, to admit steam to its upper ends, as described.

2. The piston B of a rock-drill, carrying the grooved tubular piston B', and combined with the loose nut I and ratchet-wheel d, to operate substantially as herein shown and described.'

3. The phmger J, arranged within the piston B', and connecting with the disk or plate l, to actuate the steam-valve and feed mechanism, substantially in the manner set forth.

4:. The reciprocating disk or plate l, arranged within the cylinder A, in combination with the three-pronged lever M and spring-pawl N, to actuate the slide-valve H and feed-screw D, substantially as herein shown and described.

DANIEL KENNEDY.

Witnesses: s

A. V, BRIEsEN, MICHAEL RYAN. 

